The present invention relates to a stress composite sensor and a stress measuring device using the same for a structure, for measuring stresses, such as shearing stresses, or shearing strains, produced in a structure such as an automobile, airplane, railroad vehicle, crane, robot or the like.
Methods for measuring stresses, such as shearing stresses, or shearing strains, produced in a structure such as an automobile, airplane, railroad vehicle, crane, robot or the like, include the photoelasticity method, brittle coating method, acoustic method, holographic method and strain gauge method, of which generally the strain gauge method has been used most frequently.
Such mechanical quantity sensors are various in kind and easy to handle, but when used for measuring stresses, they have to be equipped with transducers. Further, in the strain gauge method, the strain gauge is subjected to stresses in every direction and hence analysis is required.
Further, a stress sensor comprising a conventional mechanical quantity sensor such as a strain gauge, when singly used on a structure, receives greater amounts of other stresses than the main stress depending upon the position where it is attached; thus, a plurality of stress sensors have to be used and such stress sensor has to be attached to the neutral point where other stresses than the main stress are not transmitted or reduced, making it necessary to find the neutral point possessed by the structure and to attach a stress sensor to the neutral point accurately.